Work around improperly late initializing plugins

This fixes the Roland Cloud plugins.

src/plugin/plugin-bridge.cpp

@@ -229,8 +229,9 @@ PluginBridge::PluginBridge(audioMasterCallback host_callback)
 class DispatchDataConverter : DefaultDataConverter {
    public:
     DispatchDataConverter(std::vector<uint8_t>& chunk_data,
+                          AEffect& plugin,
                           VstRect& editor_rectangle)
-        : chunk(chunk_data), rect(editor_rectangle) {}
+        : chunk(chunk_data), plugin(plugin), rect(editor_rectangle) {}
 
     EventPayload read(const int opcode,
                       const int index,
@@ -239,6 +240,13 @@ class DispatchDataConverter : DefaultDataConverter {
         // There are some events that need specific structs that we can't simply
         // serialize as a string because they might contain null bytes
         switch (opcode) {
+            case effOpen:
+                // This should not be needed, but some improperly coded plugins
+                // such as the Roland Cloud plugins will initialize part of
+                // their `AEffect` only after the host calls `effOpen`, instead
+                // of during the initialization.
+                return WantsAEffectUpdate{};
+                break;
             case effEditGetRect:
                 return WantsVstRect();
                 break;
@@ -325,6 +333,14 @@ class DispatchDataConverter : DefaultDataConverter {
 
     void write(const int opcode, void* data, const EventResult& response) {
         switch (opcode) {
+            case effOpen: {
+                // Update our `AEffect` object one last time for improperly
+                // coded late initialing plugins. Hopefully the host will see
+                // that the object is updated because these plugins don't send
+                // any notification about this.
+                const auto updated_plugin = std::get<AEffect>(response.payload);
+                update_aeffect(plugin, updated_plugin);
+            } break;
             case effEditGetRect: {
                 // Write back the (hopefully) updated editor dimensions
                 const auto new_rect = std::get<VstRect>(response.payload);
@@ -423,6 +439,7 @@ class DispatchDataConverter : DefaultDataConverter {
 
    private:
     std::vector<uint8_t>& chunk;
+    AEffect& plugin;
     VstRect& rect;
 };
 
@@ -449,7 +466,7 @@ intptr_t PluginBridge::dispatch(AEffect* /*plugin*/,
         return 0;
     }
 
-    DispatchDataConverter converter(chunk_data, editor_rectangle);
+    DispatchDataConverter converter(chunk_data, plugin, editor_rectangle);
 
     switch (opcode) {
         case effClose: {